Air intake system for outboard motor

Abstract

An outboard motor air intake device having a throttle body is located essentially horizontally in front of the engine, and includes a surge tank located on a side part of the throttle body, and an air intake manifold with multiple air intake pipes which extend on one side of the engine from the surge tank to each of the cylinders. A throttle valve is located in the throttle body and the linkage mechanism that operates this throttle valve is located opposite to the engine's air intake manifold, so that the linkage is easy to assemble and maintain.

What is claimed is: 
     
       1. An outboard motor air intake device comprising: a throttle body located substantially horizontally adjacent a front surface of an engine;   a surge tank attached to the throttle body located adjacent a first side surface of the engine;   an air intake manifold located adjacent the first side surface and comprising multiple air intake pipes each extending from the surge tank to a corresponding cylinder;   a throttle valve located in the throttle body; and   a linkage mechanism to operate the throttle valve, located adjacent to a second side surface opposite the first side surface of the engine.   
     
     
       2. An outboard motor air intake device comprising: a throttle body located substantially horizontally adjacent a front surface of an engine;   a surge tank located adjacent a first side of the engine;   an air intake manifold located adjacent the first side and comprising multiple air intake pipes each extending from the surge tank to a corresponding cylinder;   a throttle valve located in the throttle body; and   a linkage mechanism to operate the throttle valve, located on a second side opposite the first side of the engine, wherein a ring gear operationally connected to a starting motor is located on a top portion of the engine, and wherein the air intake device is located below the ring gear; said air intake pipes being stacked one above the other from top to bottom on one side of the engine; and said throttle body being disposed between the midpoints of uppermost and lowermost air intake pipes.   
     
     
       3. An outboard motor air intake device comprising: a throttle body located substantially horizontally adjacent a front surface of an engine;   a surge tank located adjacent a first side of the engine;   an air intake manifold located adjacent the first side and comprising multiple air intake pipes each extending from the surge tank to a corresponding cylinder;   a throttle valve located in the throttle body; and   a linkage mechanism to operate the throttle valve, located on a second side opposite the first side of the engine, wherein the air intake pipes attach to a rear surface of the surge tank, that is formed on an oblique plane so that the bottom end of the rear surface is further backwards than the top end of the rear surface.   
     
     
       4. The outboard motor air intake device of claim 2, wherein the air intake pipes are arranged so that they are farther removed from the engine the farther downward they are positioned. 
     
     
       5. An outboard motor air intake device comprising: a throttle body located substantially horizontally adjacent a front surface of an engine;   a surge tank located adjacent a first side of the engine;   an air intake manifold located adjacent the first side and comprising multiple air intake pipes each extending from the surge tank to a corresponding cylinder;   a throttle valve located in the throttle body; and   a linkage mechanism to operate the throttle valve, located on a second side opposite the first side of the engine, wherein the width of the surge tank gradually increases from an upper width to a lower width.